【摘要】 为了考查环境土壤样品中含水量对放射性活度测量准确性的影响,采用蒙特卡罗程序MCNP4B模拟计算了当土壤样品具有不同含水量时,对不同能量γ射线用(HPGe)探测器测量效率的影响,得到了γ探测效率受含水量影响大小与样品水分含量和与γ射线能量的关系,以此关系可以得出一定含水量对不同天然放射性活度测量准确性的影响。更多还原

【Abstract】 The air drying soil samples which are sampled to survey environmental radioactivity may contain more or less water in them .In order to investigate the effect of water content on the γ detection efficiency for HPGe γ spectrometer, the Monte Carlo code MCNP4B is used to calculate the γ detection efficiency for the soil samples containing different extent of water and for different energy γ rays respectively. The relationship between the detection efficiency of γ rays charactering natural radioactive nuclides （）²³⁸U,（）²³²Th,（）²²⁶Ra,（）⁴⁰K and water content is presented in this paper.更多还原